Refrigerant metering refrigerant evaporator coil (REC) repair method

ABSTRACT

A refrigerant metering system/method incorporating a manual expansion valve (MEV), condenser isolation valve (CIV), flow isolation valve (FIV), and evaporator isolation valve (EIV) is disclosed. The MEV is configured to replace a conventional automated expansion valve (AEV) that controls a refrigerant flow valve (RFV) that is positioned in a heating, ventilation, and air conditioning (HVAC) system between a refrigerant condenser coil (RCC) and a refrigerant evaporator coil (REC) and permits manual metering of refrigerant by the RFV from the RCC to the REC and also allows complete shutoff of refrigerant flow by the RFV from the RCC to the REC. The MEV allows rapid HVAC repair and restoration of service where a replacement AEV is not readily available. The CIV/FIV/EIV are positioned in the refrigerant flow lines to permit the AEV and/or REC to be isolated from HVAC refrigerant flow for repairs to the AEV and/or REC.

CROSS REFERENCE TO RELATED APPLICATIONS Divisional Patent Application(DPA)

This is a divisional patent application (DPA) of and incorporates byreference United States Utility Patent Application for REFRIGERANTMETERING SYSTEM AND METHOD by inventor Kenneth Ray Green, filedelectronically with the USPTO on 2020 Jan. 20, with Ser. No. 16/747,422,EFS ID 38342840, confirmation number 1232, docket KRG-2020-01, issued asU.S. Pat. No. 11,428,448 on 2022 Aug. 30.

Utility Patent Applications

This patent application claims benefit under 35 U.S.C. § 120 andincorporates by reference United States Utility Patent Application forREFRIGERANT METERING SYSTEM AND METHOD by inventor Kenneth Ray Green,filed electronically with the USPTO on 2020 Jan. 20, with Ser. No.16/747,422, EFS ID 38342840, confirmation number 1232, docketKRG-2020-01, issued as U.S. Pat. No. 11,428,448 on 2022 Aug. 30.

PARTIAL WAIVER OF COPYRIGHT

All of the material in this patent application is subject to copyrightprotection under the copyright laws of the United States and of othercountries. As of the first effective filing date of the presentapplication, this material is protected as unpublished material.

However, permission to copy this material is hereby granted to theextent that the copyright owner has no objection to the facsimilereproduction by anyone of the patent documentation or patent disclosure,as it appears in the United States Patent and Trademark Office patentfile or records, but otherwise reserves all copyright rights whatsoever.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not Applicable

REFERENCE TO A MICROFICHE APPENDIX

Not Applicable

FIELD OF THE INVENTION

The present invention relates to heating, ventilation, and airconditioning (HVAC) systems, and specifically the metering ofrefrigerant within these HVAC systems. Without limitation, the presentinvention may have application in which an existing linear expansionvalve (LEV), electronic expansion valve (EEV), or thermal expansionvalve (TEV) (collectively referred to herein as automated expansionvalve (AEV)) in a HVAC system is replaced or augmented with a manualexpansion valve (MEV) in conjunction with optional condenser isolationvalve (CIV), flow isolation valve (FIV), and/or evaporator isolationvalve (EIV) in order to accommodate: (a) failure of an existing linearexpansion valve (LEV), an electronic expansion valve (EEV), a thermalexpansion valve (TEV), or an automated expansion valve (AEV) in the HVACsystem, and (b) isolation of refrigerant to a refrigerant condenser coil(RCC) or a refrigerant evaporator coil (REC) in the event of a RCC/RECfailure or other refrigerant line failure in the HVAC system.

BACKGROUND AND PRIOR ART Linear Expansion Valve (LEV) Prior Art (0100)

A conventional prior art HVAC system incorporating linear expansionvalve (LEV) refrigerant metering is generally depicted in FIG. 1 (0100).Here the refrigerant compressor (RFC) (0110) compresses refrigerant andemits same to a high side (0101) output that is fed into a refrigerantcondenser coil (RCC) (0120). A refrigerant condenser fan (RCF) (0130)generates an input air flow (0131) across the RCC (0120) and transfersheat to (from) the RCC (0120) (depending on the heating or (cooling)operation of the overall HVAC system) to generate an outside air flow(OAF) (0132) that is cooler (warmer) than the input air flow (0131)temperature. The heated (cooled) refrigerant is then transferred fromthe RCC (0120) via a refrigerant line (0102) to a refrigerant flow valve(RFV) (0140) mechanically controlled by a linear expansion valve (LEV)(0150) that meters refrigerant via RFV (0140) and transfers this meteredrefrigerant flow via a refrigerant line (0103) to a refrigerantevaporator coil (REC) (0160). A refrigerant evaporator fan (REF) (0170)takes unconditioned inside air (0171) and forces this across the REC(0160) to generate a conditioned inside air flow (0172). Refrigerantemitted from the REC (0160) is transferred via a refrigerant line (0104)to the RFC (0110) to complete the refrigerant flow within the HVACsystem.

In the event of a failure of the LEV (0150) to properly operate or meterrefrigerant via the RFV (0140), the failing LEV (0150) must be replaced.This may present problems in the field where a suitable LEV replacementpart is unavailable but the HVAC system must be promptly restored toservice. Furthermore, any refrigerant leakage associated with the REC(0160) or the incoming (0103) or outgoing (0104) refrigerant linesrequires that the entire refrigerant system be purged, repaired, andreloaded with refrigerant. Since it is common for the REC (0160) toincur pinhole leaks, this failure mechanism may result in refrigerantbeing dumped into the inside air flow (0172) causing a potential healthrisk to inhabitants of the building or structure.

Electronic Expansion Valve (EEV) Prior Art (0200)

A conventional prior art HVAC system incorporating electronic expansionvalve (EEV) refrigerant metering is generally depicted in FIG. 2 (0200).Here the refrigerant compressor (RFC) (0210) compresses refrigerant andemits same to a high side (0201) output that is fed into a refrigerantcondenser coil (RCC) (0220). A refrigerant condenser fan (RCF) (0230)generates an input air flow (0231) across the RCC (0220) and transfersheat to (from) the RCC (0220) (depending on the heating or (cooling)operation of the overall HVAC system) to generate an outside air flow(OAF) (0232) that is cooler (warmer) than the input air flow (0231)temperature. The heated (cooled) refrigerant is then transferred fromthe RCC (0220) via a refrigerant line (0202) to a refrigerant flow valve(RFV) (0240) mechanically controlled by an electronic expansion valve(EEV) (0250) that meters refrigerant via RFV (0240) and transfers thismetered refrigerant flow via a refrigerant line (0203) to a refrigerantevaporator coil (REC) (0260). A refrigerant evaporator fan (REF) (0270)takes unconditioned inside air (0271) and forces this across the REC(0260) to generate a conditioned inside air flow (0272). Refrigerantemitted from the REC (0260) is transferred via a refrigerant line (0204)to the RFC (0210) to complete the refrigerant flow within the HVACsystem.

In the event of a failure of the EEV (0250) to properly operate or meterrefrigerant via the RFV (0240), the failing EEV (0250) must be replaced.This may present problems in the field where a suitable EEV replacementpart is unavailable but the HVAC system must be promptly restored toservice. Furthermore, any refrigerant leakage associated with the REC(0260) or the incoming (0203) or outgoing (0204) refrigerant linesrequires that the entire refrigerant system be purged, repaired, andreloaded with refrigerant. Since it is common for the REC (0260) toincur pinhole leaks, this failure mechanism may result in refrigerantbeing dumped into the inside air flow (0272) causing a potential healthrisk to inhabitants of the building or structure.

Failure Mechanisms Common

The failure mechanisms associated with LEV/EEV systems as generallydepicted in FIG. 1 (0100) and FIG. 2 (0200) are commonly experienced inthe field. As such, these failures result in costly repairs as there isno mechanism in the field to quickly bypass the LEV/EEV and/or replacethe REC. To date there is a long felt need for some mechanism tosupplant a failing LEV/EEV and also provide some methodology ofservicing a HVAC system in which the LEV/EEV has failed and/or the REChas incurred a refrigerant leakage failure.

It should be noted that in some circumstances it is not the LEV/EEV thathas failed, but rather some other component associated with the HVACsystem, such as a temperature sensor or other control circuitryassociated with the LEV/EEV. In these circumstances it may not bepossible to quickly obtain replacement parts in order to return the HVACsystem to service. As such, there is a long-felt need for a repairmethodology that can provide some recovery of HVAC service until repairparts become available for a more complete service repair of the HVACsystem.

To generalize the prior art failure mechanisms, it can be seen that anynumber of automated expansion valves (AEV) (that can include LEV/EEV orequivalent thermal expansion valves (TEV)) can fail in a HVAC system andas such there is a long-felt need for a universal replacement for thesedevices that can be quickly installed to restore the HVAC system to somelevel of suitable operation while a suitable AEV replacement part can belocated and secured.

Typical Mechanical Construction (0300)-(2400)

An example of the prior art as embodied using an EEV is generallydepicted in FIG. 3 (0300)-FIG. 8 (0800) in which a refrigerantevaporator coil (REC) assembly (0360) is shown having coil fins (0361)through which refrigerant lines are coiled (0362), refrigerant inputmanifold (0363) supplying refrigerant input lines (0364), andrefrigerant output manifold (0365) retrieving refrigerant fromrefrigerant output lines (0366). Refrigerant flow in this evaporatorsystem starts from the refrigerant compressor (RFC) (not shown) (0301),flows through the evaporator system (0360), and is then transported viathe refrigerant output manifold (0365) and then taken up by therefrigerant compressor (RFC) (not shown) (0302). Refrigerant flow iscontrolled by a refrigerant flow valve (RFV) (0340) that is controlledby an automated expansion valve (AEV) that in this example is depictedas an electronic expansion valve (EEV) (0350) with electrical connector(0351) that is connected electrically to an electronic control system(ECC) (not shown) that electrically controls the operation of the EEV(0350) that in turn controls the mechanical operation of the RFV (0340).

Additional detail of the RFV (0340) and EEV (0350) from FIG. 3(0300)-FIG. 8 (0800) are depicted in FIG. 9 (0900)-FIG. 24 (2400). Hereit can be seen that the RFV (0940, 1540, 1640) and EEV (0950, 1550) areseparate components with the RFV (0940, 1540, 1640) having depictedvalve input connection port (VIP) (0941, 1541, 1641) and valve outputconnection port (VOP) (0945, 1545, 1645) respectively and a threadedvalve control port (VCP) (1549, 1649) to which the EEV (0950, 1550) ismated via a valve threaded fastener (VTF) (1559).

Operation of the RFV (1640) as generally depicted in FIG. 16 (1600) willnow be discussed. Refrigerant enters the RFV (1640) via the valve inputconnection port (VIP) (1641), routed through the input routing port(IRP) (1642), the valve transfer port (VTP) (1643), the output routingport (ORP) (1644), and exits the valve output connection port (VOP)(1645). The VTP (1643) comprises a chamber in the RFV (1640) in which avalve metering piston (VMP) (1646) meters refrigerant flow from the VIP(1641), through the IRP (1642), the VTP (1643), the ORP (1644), and tothe VOP (1645). The VMP (1646) comprises a valve control rod (VCR)(1647) that enables external control and movement of the VMP (1646) toovercome pressure applied to the VMP (1646) by a valve spring control(VSC) (1648).

In the configuration shown, the RFV (1640) is normally open, allowingrefrigerant to flow from the VIP (1641) through the VTP (1643) and tothe VOP (1645). Connection to the EEV is accomplished using a threadedport connection (TPC) (1649) on the RFV (1640) in which a seating plane(1651) mates to a corresponding plane on the EEV. A projection on theEEV exerts pressure on the VCR (1647) in order to overcome springpressure on the VMP (1646) in order to meter refrigerant flow from theVIP (1641) to the VOP (1645). As shown, the typical RFV (1640) may beconsidered a unitary valve containment structure (VCS) combining the VIP(1641), the VTP (1643), and the VOP (1645), in which the VMP (1646), VCR(1647), and VSC (1648) are positioned and in which the VCR (1647) ispositioned within a control rod port (CRP) (1652) within the RFV (1640)that allows movement of the VMP (1646) and VCR (1647) to meterrefrigerant flow from the VIP (1641) to the VOP (1645). Additionally, itcan be seen that the CRP is contained within the perimeter of thethreaded valve control port (VCP).

BRIEF SUMMARY OF THE INVENTION

The present invention pertains to a system and method wherein a HVACsystem having a failing LEV/EEV/TEV/AEV may be quickly repaired andbrought back to service while suitable replacement parts are obtained.The present invention makes use of a manual expansion valve (MEV) thatcan replace a failing LEV/EEV/TEV/AEV and permit manual control ofrefrigerant metering between the RCC and REC.

A condenser isolation valve (CIV) and flow isolation valve (FIV) thatstraddle flow through the refrigerant flow valve (RFV) allow the RFV andattached LEV/EEV/TEV/AEV to be isolated for replacement of theLEV/EEV/TEV/AEV in situations where evacuation of the HVAC system isinconvenient or not possible.

Furthermore, the REC may be isolated from the HVAC system in situationswhere the REC is failing or must be replaced. This ability to isolateREC may be implemented with the use of a flow isolation valve (FIV)between the RFV and the REC and an evaporator isolation valve (EIV)between the REC and the refrigerant compressor (RFC) such that closingthe FIV and EIV isolates the REC from the RFV/RFC and permits the REC tobe replaced with a new REC and then evacuated and recharged withrefrigerant without the need for a complete evacuation of the entireHVAC system.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the advantages provided by the invention,reference should be made to the following detailed description togetherwith the accompanying drawings wherein:

FIG. 1 illustrates a schematic depicting a prior art HVAC systemincorporating linear expansion valve (LEV) refrigerant metering;

FIG. 2 illustrates a schematic depicting a prior art HVAC systemincorporating electronic expansion valve (EEV) refrigerant metering;

FIG. 3 illustrates a top right front perspective view of a conventionalprior art HVAC evaporator coil configured with a prior art refrigerantflow valve (RFV) controlled by a prior art electronic expansion valve(EEV);

FIG. 4 illustrates a top right rear perspective view of a conventionalprior art HVAC evaporator coil configured with a prior art refrigerantflow valve (RFV) controlled by a prior art electronic expansion valve(EEV);

FIG. 5 illustrates a bottom left rear perspective view of a conventionalprior art HVAC evaporator coil configured with a prior art refrigerantflow valve (RFV) controlled by a prior art electronic expansion valve(EEV);

FIG. 6 illustrates a bottom right front perspective view of aconventional prior art HVAC evaporator coil configured with a prior artrefrigerant flow valve (RFV) controlled by a prior art electronicexpansion valve (EEV);

FIG. 7 illustrates a bottom right rear perspective view of aconventional prior art HVAC evaporator coil configured with a prior artrefrigerant flow valve (RFV) controlled by a prior art electronicexpansion valve (EEV);

FIG. 8 illustrates a bottom left rear perspective view of a conventionalprior art HVAC evaporator coil configured with a prior art refrigerantflow valve (RFV) controlled by a prior art electronic expansion valve(EEV);

FIG. 9 illustrates a front detail view of a prior art refrigerant flowvalve (RFV) controlled by a prior art electronic expansion valve (EEV);

FIG. 10 illustrates a rear detail view of a prior art refrigerant flowvalve (RFV) controlled by a prior art electronic expansion valve (EEV);

FIG. 11 illustrates a left side detail view of a prior art refrigerantflow valve (RFV) controlled by a prior art electronic expansion valve(EEV);

FIG. 12 illustrates a right side detail view of a prior art refrigerantflow valve (RFV) controlled by a prior art electronic expansion valve(EEV);

FIG. 13 illustrates a top detail view of a prior art refrigerant flowvalve (RFV) controlled by a prior art electronic expansion valve (EEV);

FIG. 14 illustrates a bottom detail view of a prior art refrigerant flowvalve (RFV) controlled by a prior art electronic expansion valve (EEV);

FIG. 15 illustrates an assembly detail view of a prior art refrigerantflow valve (RFV) controlled by a prior art electronic expansion valve(EEV);

FIG. 16 illustrates a front section perspective view of a prior artrefrigerant flow valve (RFV);

FIG. 17 illustrates a top right front perspective view of a conventionalprior art refrigerant flow valve (RFV) controlled by a prior artelectronic expansion valve (EEV);

FIG. 18 illustrates a top right rear perspective view of a conventionalprior art refrigerant flow valve (RFV) controlled by a prior artelectronic expansion valve (EEV);

FIG. 19 illustrates a top left rear perspective view of a conventionalprior art refrigerant flow valve (RFV) controlled by a prior artelectronic expansion valve (EEV);

FIG. 20 illustrates a top left front perspective view of a conventionalprior art refrigerant flow valve (RFV) controlled by a prior artelectronic expansion valve (EEV);

FIG. 21 illustrates a bottom right front perspective view of aconventional prior art refrigerant flow valve (RFV) controlled by aprior art electronic expansion valve (EEV);

FIG. 22 illustrates a bottom right rear perspective view of aconventional prior art refrigerant flow valve (RFV) controlled by aprior art electronic expansion valve (EEV);

FIG. 23 illustrates a bottom left rear perspective view of aconventional prior art refrigerant flow valve (RFV) controlled by aprior art electronic expansion valve (EEV);

FIG. 24 illustrates a bottom left front perspective view of aconventional prior art refrigerant flow valve (RFV) controlled by aprior art electronic expansion valve (EEV);

FIG. 25 illustrates a schematic depicting a preferred exemplaryembodiment of a present invention system implementing a HVAC systemincorporating manual expansion valve (MEV) refrigerant metering with acondenser isolation valve (CIV), flow isolation valve (FIV), and anevaporator isolation valve (EIV);

FIG. 26 illustrates a flowchart depicting a preferred exemplaryembodiment of a present invention method implementing a refrigerantmetering replacement method;

FIG. 27 illustrates a flowchart depicting a preferred exemplaryembodiment of a present invention method implementing a refrigerant RECrepair method;

FIG. 28 illustrates a flowchart depicting a preferred exemplaryembodiment of a present invention method implementing a refrigerantmetering maintenance method;

FIG. 29 illustrates a top right front perspective view of a preferredexemplary embodiment of a present invention system in which a HVACevaporator coil is configured with a refrigerant flow valve (RFV)controlled by a present invention manual expansion valve (MEV) and apresent invention evaporator isolation valve (EIV);

FIG. 30 illustrates a top right rear perspective view of a preferredexemplary embodiment of a present invention system in which a HVACevaporator coil is configured with a refrigerant flow valve (RFV)controlled by a present invention manual expansion valve (MEV) and apresent invention evaporator isolation valve (EIV);

FIG. 31 illustrates a bottom right front perspective view of a preferredexemplary embodiment of a present invention system in which a HVACevaporator coil is configured with a refrigerant flow valve (RFV)controlled by a present invention manual expansion valve (MEV) and apresent invention evaporator isolation valve (EIV);

FIG. 32 illustrates a bottom right rear perspective view of a preferredexemplary embodiment of a present invention system in which a HVACevaporator coil is configured with a refrigerant flow valve (RFV)controlled by a present invention manual expansion valve (MEV) and apresent invention evaporator isolation valve (EIV);

FIG. 33 illustrates a front view of a preferred exemplary embodiment ofa present invention manual expansion valve (MEV);

FIG. 34 illustrates a rear view of a preferred exemplary embodiment of apresent invention manual expansion valve (MEV);

FIG. 35 illustrates a left side view of a preferred exemplary embodimentof a present invention manual expansion valve (MEV);

FIG. 36 illustrates a right side view of a preferred exemplaryembodiment of a present invention manual expansion valve (MEV);

FIG. 37 illustrates a top view of a preferred exemplary embodiment of apresent invention manual expansion valve (MEV);

FIG. 38 illustrates a bottom view of a preferred exemplary embodiment ofa present invention manual expansion valve (MEV);

FIG. 39 illustrates a side section view and a side section perspectiveview of a preferred exemplary embodiment of a present invention manualexpansion valve (MEV);

FIG. 40 illustrates a side and perspective assembly view of a preferredexemplary embodiment of a present invention manual expansion valve(MEV);

FIG. 41 illustrates a top right front perspective view of a preferredexemplary embodiment of a present invention manual expansion valve(MEV);

FIG. 42 illustrates a top right rear perspective view of a preferredexemplary embodiment of a present invention manual expansion valve(MEV);

FIG. 43 illustrates a top left rear perspective view of a preferredexemplary embodiment of a present invention manual expansion valve(MEV);

FIG. 44 illustrates a top left front perspective view of a preferredexemplary embodiment of a present invention manual expansion valve(MEV);

FIG. 45 illustrates a bottom right front perspective view of a preferredexemplary embodiment of a present invention manual expansion valve(MEV);

FIG. 46 illustrates a bottom right rear perspective view of a preferredexemplary embodiment of a present invention manual expansion valve(MEV);

FIG. 47 illustrates a bottom left rear perspective view of a preferredexemplary embodiment of a present invention manual expansion valve(MEV);

FIG. 48 illustrates a bottom left front perspective view of a preferredexemplary embodiment of a present invention manual expansion valve(MEV);

FIG. 49 illustrates a top left front perspective view, top right frontperspective view, and top right perspective view (hiding RFV housing) ofa preferred exemplary embodiment of a present invention manual expansionvalve (MEV) mated with a conventional refrigerant flow valve (RFV) withthe MEV configured for unmetered refrigerant flow;

FIG. 50 illustrates a bottom left front perspective view, bottom rightfront perspective view, and bottom right front perspective view (hidingRFV housing) of a preferred exemplary embodiment of a present inventionmanual expansion valve (MEV) mated with a conventional refrigerant flowvalve (RFV) with the MEV configured for unmetered refrigerant flow;

FIG. 51 illustrates front side section view, front side sectionperspective view, and front side section perspective view (hiding RFVhousing) of a preferred exemplary embodiment of a present inventionmanual expansion valve (MEV) mated with a conventional refrigerant flowvalve (RFV) with the MEV configured for unmetered refrigerant flow;

FIG. 52 illustrates right side section view, right side sectionperspective view, and right side section perspective view (hiding RFVhousing) of a preferred exemplary embodiment of a present inventionmanual expansion valve (MEV) mated with a conventional refrigerant flowvalve (RFV) with the MEV configured for unmetered refrigerant flow;

FIG. 53 illustrates front side section view, front side sectionperspective view, and front side section perspective view (hiding RFVhousing) of a preferred exemplary embodiment of a present inventionmanual expansion valve (MEV) mated with a conventional refrigerant flowvalve (RFV) with the MEV configured for 50% metered refrigerant flow;

FIG. 54 illustrates right side section view, right side sectionperspective view, and right side section perspective view (hiding RFVhousing) of a preferred exemplary embodiment of a present inventionmanual expansion valve (MEV) mated with a conventional refrigerant flowvalve (RFV) with the MEV configured for 50% metered refrigerant flow;

FIG. 55 illustrates front side section view, front side sectionperspective view, and front side section perspective view (hiding RFVhousing) of a preferred exemplary embodiment of a present inventionmanual expansion valve (MEV) mated with a conventional refrigerant flowvalve (RFV) with the MEV configured for inhibited (0% metered)refrigerant flow;

FIG. 56 illustrates right side section view, right side sectionperspective view, and right side section perspective view (hiding RFVhousing) of a preferred exemplary embodiment of a present inventionmanual expansion valve (MEV) mated with a conventional refrigerant flowvalve (RFV) with the MEV configured for inhibited (0% metered)refrigerant flow;

FIG. 57 illustrates front and rear views of a preferred exemplaryembodiment of a present invention evaporator isolation valve (EIV);

FIG. 58 illustrates left side and right side views of a preferredexemplary embodiment of a present invention evaporator isolation valve(EIV);

FIG. 59 illustrates top and bottom views of a preferred exemplaryembodiment of a present invention evaporator isolation valve (EIV);

FIG. 60 illustrates top left front and top right front perspective viewsof a preferred exemplary embodiment of a present invention evaporatorisolation valve (EIV);

FIG. 61 illustrates front and rear views of an alternate preferredexemplary embodiment of a present invention evaporator isolation valve(EIV);

FIG. 62 illustrates left side and right side views of an alternatepreferred exemplary embodiment of a present invention evaporatorisolation valve (EIV);

FIG. 63 illustrates top and bottom views of an alternate preferredexemplary embodiment of a present invention evaporator isolation valve(EIV); and

FIG. 64 illustrates top left front and top right front perspective viewsof an alternate preferred exemplary embodiment of a present inventionevaporator isolation valve (EIV).

DESCRIPTION OF THE PRESENTLY PREFERRED EXEMPLARY EMBODIMENTS

While this invention is susceptible of embodiment in many differentforms, there is shown in the drawings and will herein be described indetailed preferred embodiment of the invention with the understandingthat the present disclosure is to be considered as an exemplification ofthe principles of the invention and is not intended to limit the broadaspect of the invention to the embodiment illustrated.

The numerous innovative teachings of the present application will bedescribed with particular reference to the presently preferredembodiment, wherein these innovative teachings are advantageouslyapplied to the particular problems of a REFRIGERANT METERING SYSTEM ANDMETHOD. However, it should be understood that this embodiment is onlyone example of the many advantageous uses of the innovative teachingsherein. In general, statements made in the specification of the presentapplication do not necessarily limit any of the various claimedinventions. Moreover, some statements may apply to some inventivefeatures but not to others.

HVAC Heating/Cooling Operation Not Limitive

The present invention will be described in terms of a conventional HVACheating/cooling system. In some application contexts, the system isoperated solely as a cooling system. Thus, the present invention is notlimited to heating, cooling, or heating/cooling systems, butcombinations of these configurations are also anticipated. The presentinvention may be utilize with heat pumps, heat recovery, refrigeration,and other systems that employ LEV/EEV/TEV/AEV controls and/or RECcomponents. The discussion herein does not limit the type of environmentin which the present invention may be applied.

LEV/EEV/TEV/AEV Not Limitive

The present invention will be discussed in terms of replacement of alinear expansion valve (LEV) and an electronic expansion valve (EEV).However, the present invention is not limited to these particularrefrigerant metering devices and any thermal expansion valve (TEV) maybe substituted using the disclosed invention depending on the particularapplication context. As such, the examples of LEV/EEV are only exemplaryof some situations in which the present invention may be employed.Within the context of this disclosure, the term “automated expansionvalve (AEV)” will refer to any number of the above-mentioned refrigerantexpansion valves that may be replaced temporarily or permanently by thepresent invention as described herein.

Connection Fitting Type Not Limitive

While the present invention will be described herein using componentsthat utilize soldered connections, the present invention anticipatesthat other connection fittings may be utilized on the components with noloss of generality in the invention teachings or claim scope.Specifically, the RFV and EIV described herein may incorporate a widevariety of connection fittings, including but not limited to: soldered;brazed; flared; compression; or national pipe thread (NPT). One skilledin the art will not need additional information to make thesesubstitutions based on specific application context as these connectionfittings are standards and well known in the art.

RFV Orientation Not Limitive

The refrigerant flow valve (RFV) depicted herein is configured with aninput transfer port that is configured to be perpendicular to a centraltransfer port and associated output transfer port. The present inventionanticipates that a wide variety of input/central/output portconfigurations may be utilized with the present invention without lossof generality in the invention teachings or claim scope. One skilled inthe art will not need additional information to make these substitutionsbased on specific application context, as variants of theseconfigurations are well known in the art.

Condenser Isolation Valve (CIV) Not Limitive

Some preferred exemplary invention embodiments employ a condenserisolation valve (CIV) to isolate refrigerant flow from the output of therefrigerant condenser coil (RCC) to the refrigerant flow valve (RFV). Inmany preferred embodiments this CIV is implemented as a ball valvehaving soldered, brazed, flare, or pipe thread (NPT) fittings. In somepreferred embodiments this CIV may be a MITSUBISHI ELECTRIC® brandDiamondback BV-FV Series Unibody Design Ball Valve Model selected from agroup consisting of: BV14FFSI2; BV28FFSI2; BV12FFSI2; BV58FFSI2;BB14BBSI; BB38BBSI; BB12BBSI; and BB58BBSI. While these CIVs arepreferred in many invention embodiments, they are not limitive of thescope of CIV that may be utilized in the present invention.

Flow Isolation Valve (FIV) Not Limitive

Some preferred exemplary invention embodiments employ a flow isolationvalve (FIV) to isolate refrigerant flow from the output of therefrigerant flow valve (RFV) to the refrigerant evaporator coil (REC).In many preferred embodiments this FIV is implemented as a ball valvehaving soldered, brazed, flare, or pipe thread (NPT) fittings. In somepreferred embodiments this FIV may be a MITSUBISHI ELECTRIC® brandDiamondback BV-FV Series Unibody Design Ball Valve Model selected from agroup consisting of: BV14FFSI2; BV28FFSI2; BV12FFSI2; BV58FFSI2;BB14BBSI; BB38BBSI; BB12BBSI; and BB58BBSI. While these FIVs arepreferred in many invention embodiments, they are not limitive of thescope of FIV that may be utilized in the present invention.

Evaporator Isolation Valve (EIV) Not Limitive

Some preferred exemplary invention embodiments employ an evaporatorisolation valve (EIV) to isolate refrigerant flow from the output of therefrigerant evaporator coil (REC) to the refrigerant compressor (RFC).In many preferred embodiments this EIV is implemented as a ball valvehaving soldered, brazed, flare, or pipe thread (NPT) fittings. In somepreferred embodiments this EIV may be a MITSUBISHI ELECTRIC® brandDiamondback BV-FV Series Unibody Design Ball Valve Model selected from agroup consisting of: BV14FFSI2; BV28FFSI2; BV12FFSI2; BV58FFSI2;BB14BBSI; BB38BBSI; BB12BBSI; and BB58BBSI. While these EIVs arepreferred in many invention embodiments, they are not limitive of thescope of EIV that may be utilized in the present invention.

Isolation Valve Count Not Limitive

While the present invention as discussed herein provides examples ofsystem embodiments wherein a CIV, FIV, and EIV are implemented, thepresent invention is not limited to these particular configuration andsome preferred exemplary system embodiments may have fewer than thesethree valves or combinations of less than these three valves.

Schrader/American Valve Not Limitive

While many of the CIV/FIV/EIV used in implementing the present inventionmay incorporate one or more Schrader valves (also called an Americanvalve) between the CIV/FIV/EIV refrigerant input port (RIP) andrefrigerant output port (ROP) (between which is positioned therefrigerant control valve (RCV) that allows the CIV/FIV/EIV to haltrefrigerant flow from the RIP to the ROP) to allow the refrigerant flowlines and/or REC to be evacuated and filled with refrigerant on one ormore sides of the CIV/FIV/EIV valve structure, this is not necessarily arequirement of the CIV/FIV/EIV.

The positioning of the Schrader valve in these implementations ispreferred to be between the CIV RIP and the RCC output port, the FIV ROPand the REC input port, and the EIV RIP and the REC output port. Thisconfiguration allows isolation of the RFV and/or the REC to affectrepair and/or replacement of either of these HVAC system components aswell as the AEV. These valves as positioned in the HVAC system allow theREC to be evacuated and filled with refrigerant without impacting theRFV or RCC. These valves as positioned in the HVAC system allow the AEVto be replaced and/or repaired without impacting the RFV, RCC, or REC.

However, some invention embodiments may place the Schrader valve atdifferent positions within the CIV/FIV/EIV, while other embodiments mayutilize two Schrader valves, one between the RIP and the RCV, andanother between the ROP and the RCV. While the use of Schrader valves ispreferred and these valves are well known in the art, the presentinvention is not limited to this particular type of valve in theimplementation.

Drawings Not to Scale

The drawings presented herein have been scaled in some respects todepict entire system components and their connections in a single page.As a result, the components shown may have relative sizes that differfrom that depicted in the exemplary drawings. One skilled in the artwill recognize that piping sizes, thread selections, and other componentvalues will be application specific and have no bearing on the scope ofthe claimed invention.

System Overview (2500)

A system block diagram of a present invention HVAC system incorporatingmanual expansion valve (MEV) refrigerant metering with a condenserisolation valve (CIV), flow isolation valve (FIV), and evaporatorisolation valve (EIV) is generally depicted in FIG. 25 (2500). Here therefrigerant compressor (RFC) (2510) compresses refrigerant and emitssame to a high side (2501) output that is fed into a refrigerantcondenser coil (RCC) (2520). A refrigerant condenser fan (RCF) (2530)generates an input air flow (2531) across the RCC (2530) and transfersheat to (from) the RCC (2530) (depending on the heating or (cooling)operation of the overall HVAC system) to generate an outside air flow(OAF) (2532) that is cooler (warmer) than the input air flow (2531)temperature. The heated (cooled) refrigerant is then transferred fromthe RCC (2520) via a refrigerant line (2502) to condenser isolationvalve (CIV) (2581) and then via a refrigerant line (2503) to arefrigerant flow valve (RFV) (2540) mechanically controlled by manualexpansion valve (MEV) (2550) that meters refrigerant via the RFV (2540)and transfers this metered refrigerant flow via a refrigerant line(2504) to a flow isolation valve (FIV) (2582) and then via a refrigerantline (2505) to a refrigerant evaporator coil (REC) (2560). A refrigerantevaporator fan (REF) (2570) takes unconditioned inside air (2571) andforces this across the REC (2560) to generate a conditioned inside airflow (2572). Refrigerant is emitted from the REC (2560) output port andis transferred via a refrigerant line (2506) to an evaporator isolationvalve (EIV) (2583) and a refrigerant line (2507) to the RFC (2510) tocomplete the refrigerant flow within the HVAC system.

In the event of a failure of a LEV/EEV/AEV in a typical system, thiscomponent may be removed and replaced with the MEV (2550) and the MEV(2550) may then be manually adjusted to properly meter the HVACrefrigerant flow to the REC (2560). This replacement can be affected byfirst closing the CIV (2581) and the FIV (2582) that isolates the RFVfrom the HVAC refrigerant flow loop. Once this is accomplished, thefailing LEV/EEV/AEV may be removed and replaced with a MEV (2550). Oncethe MEV (2550) is in place, the CIV (2581) and the FIV (2582) are openedand the MEV (2550) is adjusted for a nominal refrigerant flow in orderto allow the HVAC system to operate in a nominal fashion until areplacement LEV/EEV/AEV can be obtained. This ability to bring back theHVAC system to a nominal (albeit not optimal) operating point rapidly isa key advantage of the present invention over waiting for a replacementLEV/EEV/AEV component to become available.

Furthermore, any refrigerant leakage associated with the REC (2560) orthe REC (2560) incoming (2506) or outgoing (2506) refrigerant lines maybe quickly handled by fully closing both the FIV (2582) and the EIV(2583), thus isolating the REC (2560) from the HVAC refrigerationcirculation loop. Since it is common for the REC (2560) to incur pinholeleaks, this ability to isolate the REC (2560) from the HVACrefrigeration loop allows this component to be easily replaced withoutthe need for additional inside safety measures to be executed to isolatepersons from refrigerant leakage.

Refrigerant Metering AEV Replacement Method (2600)

The present invention may implement a method in which a failingLEV/EEV/AEV is replaced in the field with a MEV as described herein inorder to implement an immediate HVAC repair where replacement parts maybe currently unavailable. Here we assume that the AEV control mechanismhas failed but that the RFV is still operational, but there is no accessto a suitable AEV replacement and the HVAC system must be madeoperational before an AEV replacement can be obtained. In this AEVreplacement methodology, as generally depicted in FIG. 26 (2600), thepresent invention may be broadly generalized as a refrigerant meteringreplacement method comprising:

-   -   (1) Closing the CIV and FIV valves to isolate the RFV from the        RCC and REC (2601);    -   (2) Removing the failing LEV/EEV/AEV from the RFV control stem        (2602);    -   (3) Installing the MEV on RFV control stem (2603);    -   (4) Opening the CIV and FIV valves to connect the RFV to the RCC        and REC (2604);    -   (5) Activating the HVAC refrigerant flow (2605);    -   (6) Unlocking the MEV manual adjustment (2606);    -   (7) Adjusting refrigerant flow on the RFV using the MEV manual        adjustment (2607);    -   (8) Locking the MEV manual adjustment (2608);    -   (9) Monitoring the HVAC refrigerant temperatures at the REC        (2609);    -   (10) Determining if the REC refrigerant temperatures are within        limits, and if not, proceeding to step (6) (2610); and    -   (11) Terminating the refrigerant metering replacement method        (2611).        This general method may be modified heavily depending on a        number of factors, with rearrangement and/or addition/deletion        of steps anticipated by the scope of the present invention.        Integration of this and other preferred exemplary embodiment        methods in conjunction with a variety of preferred exemplary        embodiment systems described herein is anticipated by the        overall scope of the present invention.

Refrigerant Metering REC Repair Method (2700)

The present invention may implement a method in which a failing REC isreplaced or repaired in the field using a FIV/EIV valves as describedherein in order to isolate the REC for repair. In this REC repairmethodology, as generally depicted in FIG. 27 (2700), the presentinvention may be broadly generalized as a refrigerant metering RECrepair method comprising:

-   -   (1) Deactivating refrigerant flow in a HVAC system (2701);    -   (2) Closing a flow isolation valve (FIV) at an output port of a        refrigerant flow valve (RFV) in the HVAC system (2702);    -   (3) Closing an evaporator isolation valve (EIV) at an output        port of a refrigerant evaporator coil (REC) in the HVAC system        (2703);    -   (4) Replacing or repairing the REC (2704);    -   (5) Evacuating the REC using a Schrader port on the FIV and/or        the EIV (2705);    -   (6) Recharging refrigerant in the REC using the Schrader port on        the FIV and/or the EIV (2706);    -   (7) Opening the FIV at the output port of the RFV (2707);    -   (8) Opening the EIV at the output port of the REC (2708);    -   (9) Activating refrigerant flow in the HVAC system (2709); and    -   (10) Terminating the refrigerant metering REC repair method        (2710).        This general method may be modified heavily depending on a        number of factors, with rearrangement and/or addition/deletion        of steps anticipated by the scope of the present invention.        Integration of this and other preferred exemplary embodiment        methods in conjunction with a variety of preferred exemplary        embodiment systems described herein is anticipated by the        overall scope of the present invention.

Refrigerant Metering Maintenance Method (2800)

The present invention may implement a method in which a HVAC isretrofitted for future maintenance by using a MEV to isolate arefrigerant evaporator coil (REC) and installing a condenser isolationvalve (CIV) on the output of the refrigerant condenser coil (RCC), aflow isolation valve (FIV) on the output of the refrigerant flow valve(RFV), and an evaporator isolation valve (EIV) on the output of therefrigerant evaporator coil (REC) to allow isolation of the RFV and/orREC from the refrigerant condenser coil (RCC) and the refrigerantcompressor (RFC). This procedure allows later replacement of a failingAEV by use of the CIV and the FIV to isolate the RFV, and thus allowingthe failing AEV to be repaired or replaced. This procedure also allowslater replacement of a leaking REC by use of the FIV and the EIV toisolate the REC, and thus allowing the failing REC to be repaired orreplaced. In this maintenance methodology, as generally depicted in FIG.28 (2800), the present invention may be broadly generalized as arefrigerant metering maintenance method comprising:

-   -   (1) Deactivating HVAC system refrigerant flow (2801);    -   (2) Installing the CIV between the RCC refrigerant outlet port        and refrigerant flow valve (RFV) (2802);    -   (3) Installing the FIV between the RFV refrigerant outlet port        and refrigerant evaporator coil (REC) input port (2803);    -   (4) Installing the EIV between the REC refrigerant outlet port        and refrigerant compressor (RFC) (2804);    -   (5) Evacuating refrigerant from the REC using the Schrader ports        on the CIV and/or the FIV and/or the EIV (2805);    -   (6) Opening the CIV on the RCC to connect the RCC to the RFV        (2806);    -   (7) Opening the FIV on the RFV to connect the RFV to the REC        (2807);    -   (8) Opening the EIV on the REC to connect the REC to the RFC        (2808);    -   (9) Recharging the REC with refrigerant using the Schrader ports        on the CIV and/or FIV and/or EIV (2809);    -   (10) Activating HVAC refrigerant flow (2810); and    -   (11) Terminating the refrigerant metering maintenance method        (2811).        This general method may be modified heavily depending on a        number of factors, with rearrangement and/or addition/deletion        of steps anticipated by the scope of the present invention.        Integration of this and other preferred exemplary embodiment        methods in conjunction with a variety of preferred exemplary        embodiment systems described herein is anticipated by the        overall scope of the present invention.

Typical System Application Context (2900)-(3200)

A typical system application context for the present invention isgenerally depicted in FIG. 29 (2900)-FIG. 32 (3200) in which arefrigerant evaporator coil (REC) assembly (2960) is shown having coilfins (2961) through which refrigerant lines are coiled (2962),refrigerant input manifold (2963) supplying refrigerant input lines(2964), and refrigerant output manifold (2965) retrieving refrigerantfrom refrigerant output lines (2966). Refrigerant flow in thisevaporator system starts from the refrigerant compressor (RFC) (notshown) (2901), flows through the evaporator system (2960), and is thentransported via the refrigerant output manifold (2965) and then taken upby the refrigerant compressor (RFC) (not shown) (2902).

Refrigerant flow is controlled by a condenser isolation valve (CIV)(2981), a refrigerant flow valve (RFV) (2940) (controlled by a manualexpansion valve (MEV) (2950) that manually controls the mechanicaloperation of the RFV (2940)), a flow isolation valve (FIV) (2982), andan evaporator isolation valve (EIV) (2983).

Replacement of a failing AEV by the MEV (2950) is accomplished byclosing the CIV (2981) and FIV (2982) that allow isolation of the RFV(2940) from the HVAC system and permit replacement of the AEV by the MEV(2950) without loss of refrigerant in the HVAC system. Once the MEV(2950) is installed, the CIV (2981) and FIV (2982) can be opened and theHVAC system operated in a nominal mode until an AEV replacement can beobtained. The CIV (2981) and/or FIV (2982) may incorporate a Schradervalve (2987, 2988, 2989) to allow evacuation of the RCC (2960) and/orinsertion of refrigerant into the refrigerant loop as needed.

In addition to the replacement of the AEV with the MEV (2950), thesystem incorporates a flow isolation valve (FIV) (2982) between the RFV(2940) and the REC (2960) and an evaporator isolation valve (EIV) (2983)between the refrigerant output manifold (2965) of the REC (2960) and theRFC (not shown) that allows the REC (2960) to be isolated from the RFCfor maintenance and/or repair. The FIV (2982) and/or EIV (2983) mayincorporate a Schrader valve (2987, 2988, 2989) to allow evacuation ofthe REC (2960) and/or insertion of refrigerant into the refrigerant loopas needed.

MEV Detail (3300)-(4800)

Details of the manual expansion valve (MEV) are generally depicted inFIG. 33 (3300)-FIG. 48 (4800). Referencing the FIG. 39 (3900) sectionviews (3901, 3902) and the FIG. 40 (4000) perspective assembly views(4001, 4002), the MEV is typically composed of three (or optionallyfour) components: manual retention cap (MRC) (4051), manual control rod(MCR) (4052), manual locking fastener (MLF) (4053), and an optionalcylindrical sealing gasket (CSG) (4054).

The manual retention cap (MRC) (4051) typically incorporates one or moreouter surfaces conforming to a mechanical fastener profile, themechanical fastener profile (MFP) typically selected from a groupconsisting of: wrench flat (4055); hex nut (4056); and knurling (4091)of the outer surface of the MRC as shown. These mechanical fastenerprofiles are provided to allow the MRC (4051) to engage female threads(3992) within its control interior cavity (CIT) (3993) with male threads(1549, 1649) corresponding to a RFV threaded valve control port (VCP).The MRC female threads (3992) that conform to male threads of VCP arepresented within a control interior cavity (CIT) (3993) of the MRC andare typically formed having a fine threads-per-inch (TPI) range of 18TPI to 40 TPI or (or an equivalent metric range of 0.05 mm thread pitchto 0.15 mm thread pitch). Many preferred embodiments will utilize a 34TPI thread profile that conforms to commonly available RFV threadedvalve control ports (VCP).

The MRC (4051) comprises a threaded control port (TCP) (4094) along alongitudinal axis of the CIT. The TCP (4094) is configured to accept amanual control rod (MCR) (4052) having threads that conform to that ofthe TCP (4094). The MCR (4052) comprises a cylindrical control rod (CCR)(4057), a threaded adjustment shaft (TAS) (4058), and an adjustmentcontrol head (ACH) (4059). The CCR (4057) comprises a cylinder having acontrol rod diameter (CRD) (4095) conforming to a control rod port (CRP)(3996) within the body of the MRC (4051). As seen from the figures, theCCR (4057), the TAS (4058), and the ACH (4059) are mechanicallyconnected in a linear combination along a common longitudinal radialaxis (LRA) (4003). Adjustment of the MCR (4052) serves to move the CCR(4057) along the LRA (4003) and thus move the CCR (4057) up and down thebody of the MRC (4051). Once properly positioned along the LRA (4003),the MCR (4052) may be locked into place via use of a manual lockingfastener (MLF) (4053) that comprises a female fastening member (FFM)having a central threaded interior (CTI) (4097). The TAS (4058)comprises threads that conform to the CTI (4097) that allow the bottomface (4098) of the MLF (4053) to form a jam fit to the mechanicalfastener profile (MFP) surface (4099) of the MRC (4051). The MEV maycontain an optional sealing gasket (4054) that serves to seal the innersurface of the MRC (4051) to the top surface of the RFV threaded valvecontrol port (VCP).

The threaded adjustment shaft (TAS) (4058) may be constructed with awide range of thread profiles, but many preferred invention embodimentsutilize a fine threads-per-inch (TPI) range of 18 TPI to 40 TPI or (oran equivalent metric range of 0.05 mm thread pitch to 0.15 mm threadpitch). Many preferred embodiments will utilize a 28 TPI thread profile.

MEV Operation With RFV (4900)-(5600)

The operation of the MEV with respect to a typical RFV is generallydepicted in FIG. 49 (4900)-FIG. 56 (5600). Here it can be seen that theMCR is configured to allow adjustment of the VMP through pressureapplied to the VCR by the CCR to overcome pressure applied to the VMP bythe VSC. Additionally, the adjustment of the VMP is configured to permitrefrigerant flow from the VIP to the VOP to be adjusted from unmeteredrefrigerant flow through the RFV to zero refrigerant flow through theRFV.

FIG. 49 (4900)-FIG. 52 (5200) depict a MEV coupled with a RFV in whichthe MEV has been adjusted for unmetered (full) refrigerant flow from thevalve input port (VIP) to the valve output port (VOP). As can be seenfrom the figures, when the MEV MCR adjustment control head (ACH) isturned to the fully open position the cylindrical control rod (CCR) isretracted by virtue of the threaded adjustment shaft (TAS). Springpressure within the RFV then retracts the valve metering piston (VMP)and allows refrigerant to flow unobstructed from the VIP to the VOP.

FIG. 53 (5300)-FIG. 54 (5400) depict a MEV coupled with a RFV in whichthe MEV has been adjusted for approximately 50% (half) meteredrefrigerant flow from the valve input port (VIP) to the valve outputport (VOP). As can be seen from the figures, when the MEV MCR adjustmentcontrol head (ACH) is turned to the half open position the cylindricalcontrol rod (CCR) is mid-point positioned by virtue of the threadedadjustment shaft (TAS). Spring pressure within the RFV then retains thevalve metering piston (VMP) and allows refrigerant to flow at theselected metering rate from the VIP to the VOP.

FIG. 55 (5500)-FIG. 56 (5600) depict a MEV coupled with a RFV in whichthe MEV has been adjusted for zero (inhibited) metered refrigerant flowfrom the valve input port (VIP) to the valve output port (VOP). As canbe seen from the figures, when the MEV MCR adjustment control head (ACH)is turned to the fully closed position the cylindrical control rod (CCR)is bottomed-out by virtue of the threaded adjustment shaft (TAS). Thisin conjunction with spring pressure within the RFV then closes the valvemetering piston (VMP) and inhibits refrigerant flow from the VIP to theVOP.

The ability of the MEV to both meter refrigerant flow through the RFV aswell as completely cutoff refrigerant flow through the RFV is animportant distinction between the present invention and the prior art.Generally speaking, the LEV/EEV/AEV controls on the market lack anymethodology of completely isolating the RCC from the REC if power is notpresent in the HVAC system. For this reason it is important to be ableto perform this refrigerant isolation to allow maintenance, repair,and/or replacement of the REC. By using the MEV in this context,refrigerant flow can be manually stopped from the RCC to the REC toperform these maintenance, repair, and/or replacement operations on theHVAC system.

EIV Detail (5700)-(6400)

The present invention anticipates a wide variety of evaporator isolationvalves that may be used in various invention application contexts. Anexample of a typical EIV embodiment is generally depicted in FIG. 57(5700)-FIG. 60 (6000) with an alternate embodiment employing NPTfittings depicted in FIG. 61 (6100)-FIG. 64 (6400).

As generally depicted in FIG. 57 (5700)-FIG. 60 (6000), the EIV (6080)generally comprises a valve assembly having a refrigerant input port(RIP) (6084), a refrigerant output port (ROP) (6085) between which ispositioned a refrigerant control valve (RCV) (6086). The RCV (6086) isconfigured to allow unmetered flow of refrigerant from the RIP (6084) tothe ROP (6085) or to isolate flow of refrigerant from the RIP (6084) tothe ROP (6085) depending on the rotation of the RCV (6086) controllever. The RIP (6084) is configured to mechanically couple to theevaporator output port (EOP) and the ROP (6085) is configured tomechanically couple to a refrigerant compressor (RFC).

In some EIV configurations a Schrader valve port (6087) may bepositioned between the RIP (6084) and the RCV (6086), thus allowing theREC to be isolated from the RFC for purposes of evacuating the RECand/or recharging the REC with refrigerant. In some EIV configurations aSchrader valve port (6087) as depicted will be placed on either side ofthe RCV (6086), thus allowing the RCV (6086) to be closed and either theRFC and/or REC side of the RCV (6086) to be evacuated and/or rechargedwith refrigerant. This dual Schrader valve configuration is not depictedbut one skilled in the art will recognize that this is a simplemodification of the depicted single-Schrader valve configuration andwell within the scope of one skilled in the art to implement.

System Summary

The present invention system may be broadly generalized as a refrigerantmetering system comprising:

-   -   (a) manual expansion valve (MEV) comprising:        -   (1) manual retention cap (MRC);        -   (2) manual control rod (MCR);        -   (3) manual locking fastener (MLF);    -   wherein:    -   the MEV is configured to mechanically couple to a refrigerant        flow valve (RFV);    -   the RFV comprises a valve input port (VIP) and valve output port        (VOP) coupled together by a valve transfer port (VTP);    -   the VIP, the VOP, and the VTP are mechanically coupled in a        unitary valve containment structure (VCS);    -   the RFV comprises a valve metering piston (VMP) that is        positioned within the VTP and meters refrigerant flow between        the VIP and the VOP;    -   the VMP comprises a valve control rod (VCR) that is positioned        within a control rod port (CRP) within the VCS;    -   the RFV comprises a threaded valve control port (VCP) having        male threads;    -   the CRP is contained within the perimeter of the VCP;    -   the RFV comprises a valve spring control (VSC) acting against        the VMP to resist movement of the VMP;    -   the MRC comprises an control interior cavity (CIT) having female        threads that conform to male threads of the VCP;    -   the MRC comprises a threaded control port (TCP) along a        longitudinal axis of the CIT;    -   the MCR comprises a cylindrical control rod (CCR), a threaded        adjustment shaft (TAS), and an adjustment control head (ACH);    -   the CCR comprises a cylinder having a control rod diameter (CRD)        conforming to the CRP;    -   the CCR, the TAS, and the ACH are mechanically connected in a        linear combination along a common longitudinal radial axis        (LRA);    -   the MLF comprises a female fastening member (FFM) having a        central threaded interior (CTI);    -   the TAS comprises threads that conform to the CTI;    -   the MCR is configured to allow adjustment of the VMP through        pressure applied to the VCR by the CCR to overcome pressure        applied to the VMP by the VSC; and    -   the adjustment of the VMP is configured to permit refrigerant        flow from the VIP to the VOP to be adjusted from unmetered        refrigerant flow through the RFV to zero refrigerant flow        through the RFV.

This general system summary may be augmented by the various elementsdescribed herein to produce a wide variety of invention embodimentsconsistent with this overall design description.

Alternative System Summary

An alternative present invention system may be broadly generalized as arefrigerant metering system comprising:

-   -   (a) condenser isolation valve (CIV);    -   (b) flow isolation valve (FIV);    -   (c) evaporator isolation valve (EIV); and    -   (b) manual expansion valve (MEV) comprising:        -   (1) manual retention cap (MRC);        -   (2) manual control rod (MCR); and        -   (3) manual locking fastener (MLF);    -   wherein:    -   the MEV is configured to mechanically couple to a refrigerant        flow valve (RFV);    -   the RFV comprises a valve input port (VIP) and valve output port        (VOP) coupled together by a valve transfer port (VTP);    -   the VIP, the VOP, and the VTP are mechanically coupled in a        unitary valve containment structure (VCS);    -   the RFV comprises a valve metering piston (VMP) that is        positioned within the VTP and meters refrigerant flow between        the VIP and the VOP;    -   the VMP comprises a valve control rod (VCR) that is positioned        within a control rod port (CRP) within the VCS;    -   the RFV comprises a threaded valve control port (VCP) having        male threads;    -   the CRP is contained within the perimeter of the VCP;    -   the RFV comprises a valve spring control (VSC) acting against        the VMP to resist movement of the VMP;    -   the MRC comprises an control interior cavity (CIT) having female        threads that conform to male threads of the VCP;    -   the MRC comprises a threaded control port (TCP) along a        longitudinal axis of the CIT;    -   the MCR comprises a cylindrical control rod (CCR), a threaded        adjustment shaft (TAS), and an adjustment control head (ACH);    -   the CCR comprises a cylinder having a control rod diameter (CRD)        conforming to the CRP;    -   the CCR, the TAS, and the ACH are mechanically connected in a        linear combination along a common longitudinal radial axis        (LRA);    -   the MLF comprises a female fastening member (FFM) having a        central threaded interior (CTI);    -   the TAS comprises threads that conform to the CTI;    -   the MCR is configured to allow adjustment of the VMP through        pressure applied to the VCR by the CCR to overcome pressure        applied to the VMP by the VSC;    -   the adjustment of the VMP is configured to permit refrigerant        flow from the VIP to the VOP to be adjusted from unmetered        refrigerant flow through the RFV to zero refrigerant flow        through the RFV;    -   the CIV comprises a refrigerant input port (RIP) and a        refrigerant output port (ROP) between which is positioned a        refrigerant control valve (RCV);    -   the CIV RCV is configured to allow unmetered flow of refrigerant        from the CIV RIP to the CIV ROP or to isolate flow of        refrigerant from the CIV RIP to the CIV ROP;    -   the CIV RIP is configured to mechanically couple to a        refrigerant condenser coil (RCC) output port;    -   the CIV ROP is configured to mechanically couple to the VIP.    -   the FIV comprises a refrigerant input port (RIP) and a        refrigerant output port (ROP) between which is positioned a        refrigerant control valve (RCV);    -   the FIV RCV is configured to allow unmetered flow of refrigerant        from the FIV RIP to the FIV ROP or to isolate flow of        refrigerant from the FIV RIP to the FIV ROP;    -   the FIV RIP is configured to mechanically couple to the VOP;    -   the FIV ROP is configured to mechanically couple to a        refrigerant evaporator coil (REC) input port;    -   the EIV comprises a refrigerant input port (RIP) and a        refrigerant output port (ROP) between which is positioned a        refrigerant control valve (RCV);    -   the EIV RCV is configured to allow unmetered flow of refrigerant        from the EIV RIP to the EIV ROP or to isolate flow of        refrigerant from the EIV RIP to the EIV ROP;    -   the EIV RIP is configured to mechanically couple to a        refrigerant evaporator coil (REC) output port; and the EIV ROP        is configured to mechanically couple to a refrigerant compressor        (RFC).

This general system summary may be augmented by the various elementsdescribed herein to produce a wide variety of invention embodimentsconsistent with this overall design description.

Refrigerant Metering AEV Replacement Method Summary

A present invention refrigerant metering AEV replacement method may bebroadly generalized as a method comprising:

-   -   (1) Closing the CIV and FIV valves to isolate the RFV from the        RCC and REC (2601);    -   (2) Removing the failing LEV/EEV/AEV from the RFV control stem        (2602);    -   (3) Installing the MEV on RFV control stem (2603);    -   (4) Opening the CIV and FIV valves to connect the RFV to the RCC        and REC (2604);    -   (5) Activating the HVAC refrigerant flow (2605);    -   (6) Unlocking the MEV manual adjustment (2606);    -   (7) Adjusting refrigerant flow on the RFV using the MEV manual        adjustment (2607);    -   (8) Locking the MEV manual adjustment (2608);    -   (9) Monitoring the HVAC refrigerant temperatures at the REC        (2609);    -   (10) Determining if the REC refrigerant temperatures are within        limits, and if not, proceeding to step (6) (2610); and    -   (11) Terminating the refrigerant metering replacement method        (2611).        This general method may be modified heavily depending on a        number of factors, with rearrangement and/or addition/deletion        of steps anticipated by the scope of the present invention.        Integration of this and other preferred exemplary embodiment        methods in conjunction with a variety of preferred exemplary        embodiment systems described herein is anticipated by the        overall scope of the present invention.

Refrigerant Metering REC Repair Method Summary

A present invention refrigerant metering REC repair method may bebroadly generalized as a method comprising:

-   -   (1) Deactivating refrigerant flow in a HVAC system (2701);    -   (2) Closing a flow isolation valve (FIV) at an output port of a        refrigerant flow valve (RFV) in the HVAC system (2702);    -   (3) Closing an evaporator isolation valve (EIV) at an output        port of a refrigerant evaporator coil (REC) in the HVAC system        (2703);    -   (4) Replacing or repairing the REC (2704);    -   (5) Evacuating the REC using a Schrader port on the FIV and/or        the EIV (2705);    -   (6) Recharging refrigerant in the REC using the Schrader port on        the FIV and/or the EIV (2706);    -   (7) Opening the FIV at the output port of the RFV (2707);    -   (8) Opening the EIV at the output port of the REC (2708);    -   (9) Activating refrigerant flow in the HVAC system (2709); and    -   (10) Terminating the refrigerant metering REC repair method        (2710).        This general method may be modified heavily depending on a        number of factors, with rearrangement and/or addition/deletion        of steps anticipated by the scope of the present invention.        Integration of this and other preferred exemplary embodiment        methods in conjunction with a variety of preferred exemplary        embodiment systems described herein is anticipated by the        overall scope of the present invention.

Refrigerant Metering Maintenance Method Summary

A present invention refrigerant metering maintenance method may bebroadly generalized as a method comprising:

-   -   (1) Deactivating HVAC system refrigerant flow (2801);    -   (2) Installing the CIV between the RCC refrigerant outlet port        and refrigerant flow valve (RFV) (2802);    -   (3) Installing the FIV between the RFV refrigerant outlet port        and refrigerant evaporator coil (REC) input port (2803);    -   (4) Installing the EIV between the REC refrigerant outlet port        and refrigerant compressor (RFC) (2804);    -   (5) Evacuating refrigerant from the REC using the Schrader ports        on the CIV and/or the FIV and/or the EIV (2805);    -   (6) Opening the CIV on the RCC to connect the RCC to the RFV        (2806);    -   (7) Opening the FIV on the RFV to connect the RFV to the REC        (2807);    -   (8) Opening the EIV on the REC to connect the REC to the RFC        (2808);    -   (9) Recharging the REC with refrigerant using the Schrader ports        on the CIV and/or FIV and/or EIV (2809);    -   (10) Activating HVAC refrigerant flow (2810); and    -   (11) Terminating the refrigerant metering maintenance method        (2811).        This general method may be modified heavily depending on a        number of factors, with rearrangement and/or addition/deletion        of steps anticipated by the scope of the present invention.        Integration of this and other preferred exemplary embodiment        methods in conjunction with a variety of preferred exemplary        embodiment systems described herein is anticipated by the        overall scope of the present invention.

System/Method Variations

The present invention anticipates a wide variety of variations in thebasic theme of construction. The examples presented previously do notrepresent the entire scope of possible usages. They are meant to cite afew of the almost limitless possibilities.

This basic system, method, and product-by-process may be augmented witha variety of ancillary embodiments, including but not limited to:

-   -   An embodiment wherein the RFV comprises connection fittings        selected from a group consisting of: soldered; brazed; flared;        compression; and national pipe thread (NPT).    -   An embodiment wherein the ACH comprises a hexagonal nut profile        (HNP).    -   An embodiment wherein the MEV further comprises a cylindrical        sealing gasket (CSG) having a central hole conforming to the CRD        and a gasket diameter conforming to the RFV positioned within        the CIT and configured to seal the MRC with the RFV.    -   An embodiment wherein the MRC comprises an outer surface        conforming to a mechanical fastener profile, the mechanical        fastener profile selected from a group consisting of: wrench        flat; hex nut; and knurled surface.    -   An embodiment wherein the CIV, the FIV, and the EIV comprise a        Schrader valve positioned between the RIP and a refrigerant        control valve (RCV) contained within the CIV, the FIV, and the        EIV.    -   An embodiment wherein the CIV, the FIV, and the EIV comprise a        Schrader valve positioned between the ROP and a refrigerant        control valve (RCV) contained within the CIV, the FIV, and the        EIV.    -   An embodiment wherein the CIV, the FIV, and the EIV comprise a        first Schrader valve positioned between the RIP and a        refrigerant control valve (RCV) contained within the CIV, the        FIV, and the EIV and a second Schrader valve positioned between        the ROP and the RCV in the CIV, the FIV, and the EIV.    -   An embodiment wherein the CIV, the FIV, and the EIV comprise a        MITSUBISHI ELECTRIC® brand Diamondback BV-FV Series Unibody        Design Ball Valve Model selected from a group consisting of:        BV14FFSI2; BV28FFSI2; BV12FFSI2; BV58FFSI2; BB14BBSI; BB38BBSI;        BB12BBSI; and BB58BBSI.    -   An embodiment wherein the CIV, the FIV, and the EIV comprise        connection fittings selected from a group consisting of:        soldered; brazed; flared; compression; and national pipe thread        (NPT).

One skilled in the art will recognize that other embodiments arepossible based on combinations of elements taught within the aboveinvention description.

CONCLUSION

A refrigerant metering system/method incorporating a manual expansionvalve (MEV), condenser isolation valve (CIV), flow isolation valve(FIV), and evaporator isolation valve (EIV) has been disclosed. The MEVis configured to replace a conventional automated expansion valve (AEV)that controls a refrigerant flow valve (RFV) that is positioned in aheating, ventilation, and air conditioning (HVAC) system between arefrigerant condenser coil (RCC) and a refrigerant evaporator coil (REC)and permits manual metering of refrigerant by the RFV from the RCC tothe REC and also allows complete shutoff of refrigerant flow by the RFVfrom the RCC to the REC. The MEV allows rapid HVAC repair andrestoration of service where a replacement AEV is not readily available.The CIV/FIV/EIV are positioned in the refrigerant flow lines to permitthe AEV and/or REC to be isolated from HVAC refrigerant flow for repairsto the AEV and/or REC.

CLAIMS INTERPRETATION

The following rules apply when interpreting the CLAIMS of the presentinvention:

-   -   The CLAIM PREAMBLE should be considered as limiting the scope of        the claimed invention.    -   “WHEREIN” clauses should be considered as limiting the scope of        the claimed invention.    -   “WHEREBY” clauses should be considered as limiting the scope of        the claimed invention.    -   “ADAPTED TO” clauses should be considered as limiting the scope        of the claimed invention.    -   “ADAPTED FOR” clauses should be considered as limiting the scope        of the claimed invention.    -   The term “MEANS” specifically invokes the means-plus-function        claims limitation recited in 35 U.S.C. § 112(f) and such claim        shall be construed to cover the corresponding structure,        material, or acts described in the specification and equivalents        thereof.    -   The phrase “MEANS FOR” specifically invokes the        means-plus-function claims limitation recited in 35 U.S.C. §        112(f) and such claim shall be construed to cover the        corresponding structure, material, or acts described in the        specification and equivalents thereof.    -   The phrase “STEP FOR” specifically invokes the        step-plus-function claims limitation recited in 35 U.S.C. §        112(f) and such claim shall be construed to cover the        corresponding structure, material, or acts described in the        specification and equivalents thereof.    -   The step-plus-function claims limitation recited in 35 U.S.C. §        112(f) shall be construed to cover the corresponding structure,        material, or acts described in the specification and equivalents        thereof ONLY for such claims including the phrases “MEANS FOR”,        “MEANS”, or “STEP FOR”.    -   The phrase “AND/OR” in the context of an expression “X and/or Y”        should be interpreted to define the set of “(X and Y)” in union        with the set “(X or Y)” as interpreted by Ex Parte Gross (USPTO        Patent Trial and Appeal Board, Appeal 2011-004811, S/N        11/565,411, (“‘and/or’ covers embodiments having element A        alone, B alone, or elements A and B taken together”).    -   The claims presented herein are to be interpreted in light of        the specification and drawings presented herein with        sufficiently narrow scope such as to not preempt any abstract        idea.    -   The claims presented herein are to be interpreted in light of        the specification and drawings presented herein with        sufficiently narrow scope such as to not preclude every        application of any idea.    -   The claims presented herein are to be interpreted in light of        the specification and drawings presented herein with        sufficiently narrow scope such as to preclude any basic mental        process that could be performed entirely in the human mind.    -   The claims presented herein are to be interpreted in light of        the specification and drawings presented herein with        sufficiently narrow scope such as to preclude any process that        could be performed entirely by human manual effort.

What is claimed is:
 1. A refrigerant metering refrigerant evaporatorcoil (REC) repair method comprising: (1) Deactivating refrigerant flowin a HVAC system (2701); (2) Closing a flow isolation valve (FIV) at anoutput port of a refrigerant flow valve (RFV) in said HVAC system(2702); (3) Closing an evaporator isolation valve (EIV) at an outputport of a refrigerant evaporator coil (REC) in said HVAC system (2703);(4) Replacing or repairing said REC (2704); (5) Evacuating said RECusing a Schrader port on said FIV and/or said EIV (2705); (6) Rechargingrefrigerant in the REC using said Schrader port on said FIV and/or saidEIV (2706); (7) Opening said FIV at said output port of said RFV (2707);(8) Opening said EIV at said output port of said REC (2708); (9)Activating refrigerant flow in said HVAC system (2709); and (10)Terminating the refrigerant metering REC repair method (2710); wherein:said RFV is controlled by a manual expansion valve (MEV); said MEV isconfigured to mechanically couple to said refrigerant flow valve (RFV);said MEV manually controls mechanical operation of said RFV; said MEVcomprises: (1) manual retention cap (MRC); (2) manual control rod (MCR);and (3) manual locking fastener (MLF); said MEV mechanical coupling isconfigured to allow attachment of said MEV to said RFV in an existingheating, ventilation, and air conditioning (HVAC) system; said MEVmechanical coupling is configured to be removable and allow said MEV totemporarily replace an automated expansion valve (AEV) that has beenremoved from said RFV in said HVAC system; said RFV comprises a valveinput port (VIP) and valve output port (VOP) coupled together by a valvetransfer port (VTP); said VIP, said VOP, and said VTP are mechanicallycoupled in a unitary valve containment structure (VCS); said RFVcomprises a valve metering piston (VMP) that is positioned within saidVTP and meters refrigerant flow between said VIP and said VOP; said VMPcomprises a valve control rod (VCR) that is positioned within a controlrod port (CRP) within said VCS; said RFV comprises a threaded valvecontrol port (VCP) having male threads; said CRP is contained within theperimeter of said VCP; said RFV comprises a valve spring control (VSC)acting against said VMP to resist movement of said VMP; said VSC actionagainst said VMP acts to push said VMP against said VCR and allow flowfrom said VIP to said VOP through said VTP; said MRC comprises ancontrol interior cavity (CIT) having female threads that conform to malethreads of said VCP; said MRC comprises a threaded control port (TCP)along a longitudinal axis of said CIT; said MCR comprises a cylindricalcontrol rod (CCR), a threaded adjustment shaft (TAS), and an adjustmentcontrol head (ACH); said CCR comprises a cylinder having a control roddiameter (CRD) conforming to said CRP; said CCR, said TAS, and said ACHare mechanically connected in a linear combination along a commonlongitudinal radial axis (LRA); said MLF comprises a female fasteningmember (FFM) having a central threaded interior (CTI); said TAScomprises threads that conform to said CTI; said MCR is configured toallow adjustment of said VMP through pressure applied to said VCR bysaid CCR to overcome pressure applied to said VMP by said VSC; and saidadjustment of said VMP is configured to permit refrigerant flow fromsaid VIP to said VOP to be adjusted from unmetered refrigerant flowthrough said RFV to zero refrigerant flow through said RFV.
 2. Therefrigerant metering method of claim 1 wherein said RFV comprisesconnection fittings selected from a group consisting of: soldered;brazed; flared; compression; and national pipe thread (NPT).